ΔH reaksi = ∑ energi reaksi -∑ energi ikatan produk.
= [(4
mol C-H+2 mol o2o)-(2 mol C₂O+4 mol O-H)] KJ
=
[(1.652 KJ + 990 KJ)-(1.598 KJ+1.852 KJ)]
= 2.642
KJ – 3.450 KJ
= -808
KJ.